JPH0445076B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a device for detecting a decrease in the capacity of a storage battery mounted on an automobile or two-wheeled vehicle.

BACKGROUND OF THE INVENTION Motorcycles have recently become widespread, and their user base has spread over a wide range of areas. In particular, as the number of female users has increased, the majority of methods for starting motorcycles have shifted from the kick type to the starting method using starter motors similar to those used in automobiles. In the case of the kit type, it was possible to start and run without a storage battery, so
The existence value of storage batteries was not very great, but as the starting method shifted to cell-based starting methods, the importance of storage batteries became recognized, especially when the combination of electric and cell methods was changed to single-starting methods using cell-based starting methods. It has become essential to develop a storage battery condition detection device to detect storage battery troubles before they occur.

The development of storage battery status detection devices is active for both automobiles and motorcycles, but both batteries are compact, and motorcycle batteries in particular have a small liquid opening and a small amount of electrolyte, so it is difficult to detect changes in battery voltage. The main method is to detect the capacity state or charge state, and a sensor is directly inserted into the battery liquid opening.
It can be said that there is no method to detect the specific gravity of the electrolyte.

Many of the storage battery capacity determination methods based on voltage changes that have been introduced in the past detect the drop in voltage during cranking, where the voltage change is the largest. A method of forcibly applying a load and determining the capacity state of a storage battery based on the voltage drop caused by the load is introduced.

However, when examining the correlation between storage battery capacity and voltage trends, we find that even if the cranking voltage is high, the spare capacity may be small, or even if the electromotive force is high, the cranking voltage may drop abnormally. Determining the battery condition based on just one factor can be dangerous.

It is well known that a more accurate storage battery capacity detection device can be constructed by considering not only the voltage during discharging but also the voltage during charging, but since detecting various factors would complicate the circuit, it is not currently introduced. Many of the capacitance detection devices currently available are based on one factor.

Means for Solving the Problems The present invention eliminates the drawbacks of the capacity detection device due to one factor as described above, and provides a storage battery monitoring device for automobiles and motorcycles that can detect the capacity of the storage battery from any state of the storage battery.

That is, the present invention provides a first voltage dividing point for detecting voltage during cranking, a second voltage dividing point for detecting voltage during running, and a third voltage dividing point for detecting voltage during no-load. A voltage dividing resistor circuit for detecting storage battery voltage, which is configured such that the detection voltage during cranking, the detection voltage during running, and the detection voltage during no load of the storage battery in the same discharge state are the same. A diode is connected between the first voltage division point and the linear IC so that its positive terminal side becomes the input terminal side of the linear IC, and is used to detect the voltage during cranking. It is a series circuit of a diode and a resistor connected between the second voltage dividing point and the linear IC so that the positive terminal side becomes the input terminal side of the linear IC. A high resistance connected between the third voltage dividing point and the linear IC to detect the voltage under no load, and a voltage dividing resistor circuit for detecting storage battery voltage. The capacitor is configured to store the minimum voltage detected during cranking or driving for a certain period of time, and to be charged by the detected voltage during no-load conditions, and the number of lights on increases or decreases depending on the voltage level of the capacitor. The present invention is characterized in that the storage battery state detection device is equipped with an LED and is capable of monitoring the charging/discharging state level of the storage battery based on the number of lit LEDs.

Embodiment Hereinafter, an embodiment of the apparatus of the present invention will be described in detail with reference to the drawings.

In the figure, resistors r1 and r connected in series
2, r3, and r4 are connected between both terminals of the storage battery 1, and form a storage battery voltage detection circuit that detects changes in cranking voltage, load voltage, and no-load voltage at midpoints a, b, and c of each resistor. are doing. The intermediate points a, b, and c are connected to a series circuit of a diode Si1, a diode Si2, and a resistor r5, and a resistor r6, respectively.
connected to one terminal of capacitor C via
The other terminal of the capacitor is connected to the negative electrode of the storage battery 1. Furthermore, the input terminal of the linear IC 2 is connected so that the charging voltage of the capacitor C is applied thereto, and the LEDs 1 to 5 are connected between each output terminal 1 to 5 and the positive terminal of the storage battery 1, respectively. .

Although the no-load voltage (electromotive force) of the storage battery, the voltage during driving (mainly during light loads such as main lights and brake lights), and the voltage during cranking and the storage battery capacity have different proportional constants, they have an almost linear proportional relationship. I have it. Since these three different factors cannot be displayed on the same display device, the circuit must be configured so that the voltages of these three factors are equivalent. For example, if the no-load voltage is 12V, the load voltage is 11V.
, and when the cranking voltage is 8V, the battery is completely discharged, although the voltages are different. When the storage battery reaches the above voltage in each state, if the same voltage can be applied to the input of the LED lighting linear IC, unified display can be achieved.

In order to obtain the above conditions, the storage battery voltage is divided by series resistors r1 to r4, and point a is the voltage detection point during cranking, point b is the load voltage detection point, and point c is the no-load voltage detection point. When the voltage Vin of the input terminal of linear IC2 for LED lighting increases, the output terminal becomes 1.
The number of LEDs will turn ON sequentially, and the number of LEDs will increase. Suppose now that when Vin=0 [V], LED1 is turned off and only LED0 is turned on, indicating the storage battery discharge state. In this case, if the voltage of the constant voltage diode ZD is set to 5 [V], the following equation holds true.

At no load Vin=12r4/(r1+r2+r3+r4)-5 At load Vin=11(r3+r4)/(r1+r2+r3+r4)/-5 At cranking Vin=8(r2+r3+r4)/(r1+r2+r3+r4)-5 All of the above Vins are 0[ V], so r
If the resistance values of 4 are arbitrarily determined, r1, r2, r
The resistance value of 3 is calculated by calculation. Next, diode Si1 is inserted between voltage detection point a during cranking and the input terminal of linear IC2 to prevent charging of capacitor C from point a during no load and to prevent the voltage at point a from dropping. This is to instantly discharge the charge in the memory capacitor C and memorize the lowest voltage during cranking. Similarly, diode Si2 and resistor r5 are inserted between the running voltage detection point b and the input terminal of linear IC2.
This is to prevent charging of the capacitor C from point b during no load and to provide a delay time long enough to prevent voltage drop during cranking from being sensed. In other words, the cranking time is often about 3 seconds or less, and the load time (main lights, brake lights, etc.) is often more than 1 minute, so the time constant due to r5+C is 1.
About a minute is appropriate. A high resistance r6 is inserted between the no-load voltage detection point c and the input terminal of the linear IC2,
No-load voltage is always applied to capacitor C. The reason why a high resistance is inserted here is that capacitor C, which stores the lowest voltage, is instantly charged through resistor r6 when the voltage increases due to cranking release, etc., so that the alarm timing is not missed. This is to ensure that the time constant due to r6 is also 1 minute or more.

In the above device, when a voltage drop occurs due to a decrease in capacity during no-load, driving, or cranking, capacitor C memorizes these voltages.
The state of charge of the storage battery can be displayed by reducing the number of LEDs lit and gradually canceling the capacity reduction display as the charging voltage increases during driving.

Note that the display method in the figure is just an example;
If you use more than one, you can freely configure the display section. That is, the central part of the display shows the normal state of the storage battery, the left side shows the discharged state of the battery, and the right side shows the charged state, making it easy to see what state the battery is in.

Effects of the Invention As described above, the present invention detects the storage battery capacity based on three factors: voltage during cranking, voltage drop due to load during running, and no-load voltage (electromotive force). In this way, false detection due to one factor detection can be prevented, and since the charging state can also be displayed, a more accurate storage battery state can be grasped.

[Brief explanation of drawings]

The figure is a circuit diagram showing an embodiment of the storage battery monitoring device of the present invention. 1...Storage battery, 2...Linear IC, C...Capacitor, r1 to r4...Resistance for voltage division.

Claims (1)

[Claims] 1. A first voltage dividing point a for detecting voltage during cranking, a second voltage dividing point b for detecting voltage during running,
A voltage dividing resistor circuit r1, r for detecting storage battery voltage, comprising a third voltage dividing point c for detecting voltage during no-load.
2, r3, and r4, which are configured so that the detection voltage during cranking, the detection voltage during running, and the detection voltage during no-load of storage batteries in the same discharge state are the same; A diode Si1 is connected between the voltage dividing point a and the linear IC2 so that its positive terminal side is on the input terminal side of the linear IC2, and is for detecting the voltage during cranking; It is a series circuit of a diode Si2 and a resistor r5 connected between the voltage dividing point b and the linear IC2 so that its positive terminal side becomes the input terminal side of the linear IC2, and is used to detect the voltage during running. A high resistance r6 connected between the third voltage dividing point c and the linear IC2 for detecting the voltage at no load, and a voltage dividing resistor circuit for detecting the storage battery voltage. The capacitor C is configured to store the minimum voltage during cranking or running for a certain period of time, and to be charged by the detected voltage during no-load conditions, and the number of lights lit increases or decreases depending on the voltage level of the capacitor C. A storage battery status detection device comprising a LED (LED) and